New objects shown at South By Southwest Interactive will be shiny whether or not the sun comes out in Austin, Texas.

My message to marketers: beware.

I’m not anti-innovation. Quite the contrary, in fact. I’m in tech as much for the unknown as the known. But let’s concentrate on the known for a minute. The estimated 30,000 going to Austin are not the norm (in more ways than one). We seemingly all carry iPhones and Macs, and many of us check in on Foursquare.

The norm is likely your brand’s target — about half of U.S. mobile subscribers don’t yet carry a smartphone, much less line up to buy a Mac. Their idea of a check-in involves questions of smoking versus non-smoking, a room away from the elevator, and the time the buffet opens in the morning.

What we saw at the Austin Convention Center and environs last year were early-adopter models, ones that caused a ripple on Twitter but not so much on Main Street.

The geo-location startups came into a marketplace that today shows only 30 million global users of leader Foursquare (for perspective, there are well over 300 million mobile subscribers in the United States alone and more than 6 billion worldwide).

So what is a brand manager to do? The smartest ones are relying on a mix of products and services that aren’t necessarily aimed at early adopters. Ford employs a variety of mobile strategies and tactics, including a text call to action in traditional media that produced a 15.4 percent lead conversion. An influencer on Twitter described the program as “meat and potatoes.” As a CMO who hasn’t touched beef in decades, I’ll dine on “meat and potatoes” all day and all night for such lead success.

We’ll certainly again hear lots this year about the mobile wallet. There surely will be hype around near field communication. But cash gone by Tuesday? Ummm, no.

So what should we do in Austin? Live. Learn. But don’t jump in blindly, sunshine or not.